Alloy steel



Patented June 17, 1924.

'UNITED STATESPATENT OFFICE.

W NOBMAN BRATTON, OF NEW YORK, N. Y., ASSIGNO'B T0 CLIMAX MOLY'BDENUM COMPANY, OF NEW YORK, N. Y.,

A CORPORATION or new YORK.

Armor s'rm.

No Drawing.

To all whom, it may concern:

Be it known that I, W NORMAN BRATTON, a citizen of the United States, residing at New York, in the county of New York, State invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements in alloy steels and provides'a commercial composition of alloy steel presenting many ad.- vantages.

The improved alloy steel of the present invention is a manganese steel containing a' case of plain carbon steel.

relatively high content of manganese, e. g. from 1 to 2.5%, and also contaming'nickel and molybdenum.

It has heretofore been proposed to add nickel to manganese steels, but with nickel and manganese alone, the steel has a limited range of treatment which it is necessary to control carefully, and segregation often" reduces or nullifies the improved physical properties.

The improved alloy steel of the present invention is an improvement upon nickelmanganese steels, possessing improved physical properties, and making these improved properties available for commercial uses. The limitations and disadvantages of nickelmanganese steels are overcome, the range of treatment is widened out, and danger of segregation relieved, through the incorporat1on of molybdenum in the nickel-manganese steel.

The new alloy steels in general contain from 1 to 2.5% manganese, from a fraction of a per cent up to about 1.25% of molybdenum, and from a fraction of a per cent up to about 3.5% nickel.

The steel may contain varying-amounts of the other usual ingredients such as carbon, silicon," etc., and mayalso contain other alloying metals.

The new alloy steel has the advantage froma manufacturing standpoint that two of the elements, molybdenum and nickel, are practically loss proof with both basic-and acid slags so that the molybdenum and nickel may be added at the outset and may remaln' in the molten metalithroughoutthe manufacture of the steel, or they may be Application filed December 5, 1923. Serial No. 678,788:

added during theprocessof manufacture and before the process is completed. .Con- 'sequently, when the steel is ready to be tapped, and when the molybdenum and nickel have been .already added, the only calculations and additions necessary are for giving to the steel the desired content of manganesa'and the desired content of other ingredients such as carbon and silicon. These additions at the time of tapping simplify the steel making process and make it similar to a plain carbon steel process. That is, the molybdenum and nickel can be added in the desired amountsduring the furnace process, and themanganese, carbon and silicon can be added as the result of a final calculation similar to that employed'in the This simple process nevertheless enables the desired molybdenum-nickel-manganese steel to be produced with a high manganese content and with thedesired content of molybdenum and nickel, while it also permits the content of other ingredients such as carbon and silicon to be regulated and controlled.

Nickel toughens the steel and manganese strengthens it, while the nickel and manganese throughout the steel amplify the toughness, strength and resistance to wear-producing properties of the highly active molybdenum, or vice versa, or these three metals otherwise interact with each other and with the other ingredients of the steel to give the improved physical properties,

such as toughness and strength. Nickel and. manganese lower the temperature at Wl'llCh the carbon changes from one state (austenite)- to another state (pearlite), which ac' tion is one of the responsible causes for setting and deepening of the hardening effect; while molybdenum strongly intensifies the hardening effect. Molybdenum and manganese are also highly powerful ele-' ments in delaying the dissociation of the hardening carbon condition.

One of the advantages of this, carbon condition in the steel is the resistance to wear of the surface of the steel,

especially under conditions where the surface is'heated. Another advantage of the stability of this carbon condition in the steel is that cooling strains within the steel are relieved by the time and heat necessary to dissociate, this carbon condition. Another important advantage is the finely divided the stability bf,

properties can be produced at low cost andv by a simple method of manufacture, containing a small percentage of molybdenum,

a small percentage of nickel, and a high per centage of manganese.

- the molybdenum, nickel and manganese may While the proportions of molybdenum,

'nickel and manganese in the new alloy steel can be varled, it is advantageous for manypurposes, to have the nickel content higher than the manganese content, or higher than the molybdenum content, or to have the molybdenum contenthigher than the nickel content. Where cost is not a controlling conmolybdenum, nickel andmanganese will be where the improved physical properties of the molybdenum-nickel-manganese combinations decline.

The carbon content of the new alloy steels can vary from a fraction of 1% up to in excess of 1%. For softer steels a carbon content of from for example 0.1 or 0.2% up to 0.5 or 0.8% can be used. For other purposes a higher carbon content can be used, e. g. around 1% or from about 0.8 to about 1.4%, giving a harder steel; While for still harder steels the carbon content may be increased above 1.4% up to an amount approximating the cast iron range. r

The silicon content of the alloy can also be varied and regulated. The alloy may contain only the normalcontent of steels or a small increase thereover, e. g. from less than 0.1% up to 0.2% or 0.4%; or a much higher silicon content. may be used, e. g. around 0.75% or 1%, or even higher.

The steel will also contain the impurities present in small amount in commercial steels such as sulfur, phosphorus, etc. The steel may be deoxidized with suitable deoxidizers and commercial deoxidizers may be used for this purpose, or special deoxidizers such as zirconium, etc., may be used. The alloy steel may also contain varying amounts of other alloyin metals in addition to the nickel, molyb enum and manganese.

The invention will be further illustrated by the following specific examples of com-' positions or ratlos of the ingredients suit-' able for wide usages.

When the molybdenumcontent is about 0.25%, the ratio of advantageously be about 1:4: 6, that is, contaming about 1% of nickel and about 1.5% of manganese. Instead of using the molybdenum, nickel and manganese in these promolybdenum. sideration, the limiting percentages of portions, the molybdenum may be for ex-.

ample about 0.25%, the nickel about 0.5% or. less, andthe manganese about 1.5%.

Another advantageous ratio of the molybdenum nickel and manganese, where the molybdenum content is about 0.5%, is the ratio of 1:2:3, thatis, with about 1% of nickel and about 1.5% of manganese. In-

. The combination of alloys in the proportions used in these specific examples are low in cost of manufacture and possess important properties in the way of toughness,

strength, wide range of heat treatment, etc.

I claim:

1. An alloy steel containing about 1% to 2%% of manganese'and also containing small but substantial amounts of nickel and 2. An alloysteel containing about 1% to 2%% of manganese and also containing nickel and molybdenum in small but substantial amounts, both the nickel and molybdenum contents being less thanthat of the manganese.

3. An alloy steel containing from a small but substantial fraction of 1% up to about 1.25% of molybdenum, from a small'but substantial fraction of 1% up to about 3.5%

manganese.

4. An alloy steel containing from a'sma-ll but substantial fraction of 1% up to about 1.25% of molybdenum, from. a small but substantial fraction of 1% up to about 3.5% of nickel, from 1% to about 2.5% of manganese, and containing up to about 0.8% of carbon.

5. An alloy steel containing from a small but substantial fraction of 1% up to about 1.25% of molybdenum, from a small but substantial fraction of1% up to about 3.5% of nickel, from 1% to about 2.5% of manganese, and containing from about 0.8% to about 1.4% of carbon. 1

6. An alloy steel containing from a small but substantial fraction of 1% up to about 1.25% of molybdenum, from a small butsubstantial fraction of 1% up to about 3.5% of nickel, from 1% to about 2.5% of manganese, and containing a carbon content in excess of 1.4%.

7 An alloy steel containing. molybdenum, nickel and manganese in small but substan tial amounts, the nickel content being in excess of the molybdenum content, and the -of nickel and from 1% to about 2.5% of being in excess of the molybdenum content and the manganese content bein in excess of both the nickel and the molyb enum contents together, the manganese content being from about 1% to about 2}%, and the molybdenum and nickel being present in small but substantial percentages.

9. An alloy steel containing molybdenum nickel and manganese in the proportions of about 1 part of molybdenum, 1 to 4 parts of nickel, and 3 to 6 parts of manganese, the molybdenum being present in amounts varying from a small but substantial fraction of 1% up to about 1.25%.

10. An alloy steel containing molybdenum,

nickel and manganese in the proportions of 1 part of molybdenum, 2 to 4 parts of nickel, and 3 to 6 parts of manganese, the

molybdenum bein present in amount-s varying from a smal but substantial fraction of 1% up to about 1.25%.

11. An alloy steel containing molybdenum, nickel and manganese in the proportions of about 1 part of molybdenum, 6 parts of manganese, and from 4 to less than 2 parts of nickel, the molybdenum being present in amounts varyin from a small but substantial fraction 0 1% up to about 1.25%.

12. 'An alloy steel containing molybdenum, nickel and manganese in the proportions of about 1 part of molybdenum, 3 parts of manganese, and 2 or less than 2 parts of nickel, the molybdenum being present in amounts varying from a small but substantial fraction of 1% up to about 1.25%.

13. An alloy steel containing about 0.25% molybdenum, about 1.5% manganese, and up to about'1% of nickel.

14. An alloy steel containing about 0.5% molybdenum, about 1.5% manganese, and up to about 1% of nickel.

In testimony whereof I afix my signature.

W NORMAN BRATTON. 

